From: John Baez <baez@math.ucr.edu>
To: categories <categories@mta.ca>
Subject: spans in 2-categories
Date: Tue, 19 Aug 2008 07:45:12 -0700 [thread overview]
Message-ID: <E1KVUXk-0005Wd-OJ@mailserv.mta.ca> (raw)
Dear Categorists -
Given a category C with pullbacks we can define a bicategory Span(C)
where objects are objects of C, morphisms are spans - composed
using pullback - and 2-morphisms are maps between spans.
Have people tried to categorify this yet?
Suppose we have a 2-category C with pseudo-pullbacks. Then we should
be able to define a tricategory Span(C). Has someone done this?
Or maybe people have gotten some partial results, e.g. in the case
where C = Cat. I'd like to know about these!
Best,
jb
reply other threads:[~2008-08-19 14:45 UTC|newest]
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